Uganda’s police chief has blocked presidential hopeful Amama Mbabazi from holding public meetings across the country, saying they are “illegal”.

Inspector General of Police, Kale Kayihura, wrote to Mbabazi on Tuesday informing him of the decision.

Sacked prime minister Mbabazi, 66, announced last week he would challenge his former ally President Yoweri Museveni, 70, in elections due next year.

Museveni has already been given the green light as candidate for the ruling National Resistance Movement (NRM) by the party’s top body, but Mbabazi, a fellow party stalwart, wants to challenge Museveni to become NRM flag bearer in 2016.

Describing himself as an “aspiring candidate for president” Mbabazi told the electoral commission that he intended to hold “nationwide consultations” during July.

In response, the country’s police chief wrote that “it is clear that your party has neither sponsored nor endorsed you as an aspirant within the meaning of the NRM Constitution and law… and that your aspirations are illegal.”

“In view of the above, your programme of public meetings are not cleared by the police and cannot go ahead,” Kayihura wrote in his letter, dated June 23.

Mbabazi’s spokesperson, Josephine Mayanja-Nkangi, said his lawyers would respond.

“The Inspector General of Police is fully aware of the law, therefore this little tantrum is merely diversionary,” she said.

Uganda’s Public Order Management Act requires police notice for demonstrations, among other things.

At least 30 supporters of Mbabazi were arrested between Monday and late last week, it has been reported.